Microwave-assisted cascade exploitation of giant reed (Arundo donax L.) to xylose and levulinic acid catalysed by ferric chloride

• Published in: Bioresource technology 2019-12, Vol.293, p.122050-122050, Article 122050
• Main Authors: Di Fidio, Nicola, Antonetti, Claudia, Raspolli Galletti, Anna Maria
• Format: Article
• Language: English
• Subjects: Arundo donax L; FeCl3; Levulinic acid; Microwave; Second generation sugars
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2019.122050

[Display omitted] •MW-assisted hydrolysis of Arundo donax L. was investigated.•Two-steps hydrolysis catalysed by FeCl3 was optimized.•The highest xylose yield was 98.2 mol% respect to xylan.•The highest levulinic acid yield was 57.6 mol% respect to glucan.•This cascade approach allowed the extensive valorisation of carbohydrates. The present work aimed to investigate and optimize the selective exploitation of hemicellulose and cellulose fractions of the energy crop Arundo donax L. (giant reed), to give xylose and levulinic acid, respectively. In order to improve the sustainability of this process, a microwave-assisted hydrolysis in the presence of FeCl3 was implemented using as substrate the raw biomass without any pretreatment process. The effects of the hydrolysis reaction conditions, such as temperature, reaction time, salt amount and biomass loading, on giant reed exploitation were investigated. In the first step, under the optimized conditions (150 °C, 2.5 min and 1.6 wt% FeCl3), the xylose yield reached 98.2 mol%. In the second step, under the best conditions (190 °C, 30 min and 2.4 wt% FeCl3), the levulinic acid yield was 57.6 mol%. This novel cascade approach ensured an extensive exploitation of giant reed polysaccharides working in the respect of Green Chemistry principles.